/*
 * Copyright 2020 eBlocker Open Source UG (haftungsbeschraenkt)
 *
 * Licensed under the EUPL, Version 1.2 or - as soon they will be
 * approved by the European Commission - subsequent versions of the EUPL
 * (the "License"); You may not use this work except in compliance with
 * the License. You may obtain a copy of the License at:
 *
 *   https://joinup.ec.europa.eu/page/eupl-text-11-12
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * permissions and limitations under the License.
 */
package org.eblocker.server.common.pubsub;

/**
 * A service for subscribing to and publishing messages in channels.
 */
public interface PubSubService {
	/**
	 * Publish a message in a channel
	 * @param channel
	 * @param message
	 */
	void publish(String channel, String message);
	
	/**
	 * Subscribe to a channel. This method never returns, so it should be run in a
	 * background thread.
	 * @param channel
	 * @param subscriber
	 */
	void subscribeAndLoop(String channel, Subscriber subscriber);

	void unsubscribe(Subscriber subscriber);
}
